Such mechanisms are often installed in sailboats and the like and are identified as an auxiliary drive therefor. However, they can be used also as a primary drive for smaller motor boats and for lateral thrust rudders and the like in smaller ships.
In a known construction (Motor Boat and Yachting, November 1977, Page 13) the drive motor is flange connected to a gear housing having a gearing aggregate therein, which contains two cone-pulley drives. The entire unit is secured on a base plate which is connected to the hull, which base plate--just like the hull--has an opening therethrough through which projects the gearing aggregate and the propeller which is arranged on its driven shaft. This compact manner of construction of the drive mechanism permits a removal of the motor only with the gearing aggregate attached thereto. Thus, the removal cannot take place as long as the boat is in the water. In addition, the propeller thrust is transmitted onto the hull through the screws which hold the entire drive mechanism to the hull.
A different design, in which the drive motor is arranged above the gearing aggregate (German OS No. 25 25 838) has principally the same disadvantages.
Therefore, the basic object of the invention is to provide a drive mechanism for watercrafts, in which the aggregates which are arranged within and outside of the hull can be secured independently from one another in or on the watercraft and in particular the drive motor can be installed and removed also when the vessels are in the water. Furthermore, the propeller thrust is transmitted via a short route onto a base plate secured to the hull.
It is suggested in order to attain the object to secure the drive motor and a first angle gear arrangement having a downwardly driven shaft resiliently to a base plate which closes off an opening in the hull, while the lower part which includes a second angled gear arrangement, the horizontally extending driven shaft carries the propeller, is secured rigidly to the base plate. The power transmission from the upper part to the lower part is accomplished through an elastic coupling arranged therebetween. By deleting the first angled gear arrangement, this arrangement can also be used when a drive motor having a downwardly directed driven shaft is used.
The upper part is secured preferably from the inside of the boat and the lower part from the outside. When the lower part is mounted in various positions with respect to the upper part, the possibilities of use of the device are increased.
Good operating results are brought about by couplings having universal joint characteristics and wherein the coupling is protected by a sleeve.
The installation of the base plate into the hull is substantially eased if it is centered in the hull. At least in the cases, where an internal combustion engine is used as a drive motor, the first angled gear arrangement is a reversing gear.